1. Field of the Invention
Exemplary aspects of the present invention generally relate to a cleaning device that cleans a surface of an image carrier, a process cartridge including the cleaning device, and an image forming apparatus including the process cartridge, and more particularly to a cleaning device including a lubricant supply roller that supplies a lubricant to a surface of an image carrier, a process cartridge including the cleaning device, and an image forming apparatus including the process cartridge.
2. Description of the Background
Related-art image forming apparatuses, such as copiers, printers, facsimile machines, and multifunction devices having two or more of copying, printing, and facsimile functions, typically form a toner image on a recording medium (e.g., a sheet of paper, etc.) according to image data using an electrophotographic method. In such a method, for example, a charger charges a surface of an image carrier (e.g., a photoconductor); an irradiating device emits a light beam onto the charged surface of the photoconductor to form an electrostatic latent image on the photoconductor according to the image data; a developing device develops the electrostatic latent image with a developer (e.g., toner) to form a toner image on the photoconductor; a transfer device transfers the toner image formed on the photoconductor onto a sheet of recording media; a cleaning device removes residual toner from the surface of the photoconductor, and a fixing device applies heat and pressure to the sheet bearing the toner image to fix the toner image onto the sheet. The sheet bearing the fixed toner image is then discharged from the image forming apparatus.
There is known an image forming apparatus using a cleaning device that reliably removes foreign substances such as untransferred toner from an image carrier and a lubricant supply roller that supplies a lubricant to the image carrier to prevent abrasion of the image carrier, a cleaning blade, and so on.
Specifically, the lubricant supply roller supplies a lubricant to a photoconductor serving as the image carrier. The image forming apparatus further includes a cleaning blade provided upstream from the lubricant supply roller in a direction of rotation of the photoconductor to contact a surface of the photoconductor against the direction of rotation of the photoconductor, and a leveling blade provided downstream from the lubricant supply roller to contact the surface of the photoconductor against the direction of rotation of the photoconductor.
In such an image forming apparatus, untransferred toner remaining on the surface of the photoconductor is removed by the cleaning blade, and then the lubricant supply roller supplies the lubricant to the cleaned surface of the photoconductor. Thereafter, the leveling blade levels the lubricant thus supplied to the surface of the photoconductor so that the photoconductor is covered with a layer of lubricant of uniform thickness.
In the related-art image forming apparatus, the leveling blade may chatter, curl, or abrade even in a case in which the lubricant is sufficiently supplied to the surface of the photoconductor by the lubricant supply roller. Specifically, unstable and insufficient supply of the lubricant to the surface of the photoconductor using the lubricant supply roller increases frictional resistance between the leveling blade and the surface of the photoconductor. However, even in a case in which the lubricant is sufficiently supplied to the surface of the photoconductor by the lubricant supply roller, the lubricant thus supplied may be dissolved and deteriorate to have a large viscosity due to high-voltage electrical discharge from the charger that charges the surface of the photoconductor. Consequently, frictional resistance between the leveling blade and the surface of the photoconductor may be increased, possibly causing the leveling blade to chatter, curl, or abrade.